/*
 *
 *  * Licensed to the Apache Software Foundation (ASF) under one or more
 *  * contributor license agreements.  See the NOTICE file distributed with
 *  * this work for additional information regarding copyright ownership.
 *  * The ASF licenses this file to You under the Apache License, Version 2.0
 *  * (the "License"); you may not use this file except in compliance with
 *  * the License.  You may obtain a copy of the License at
 *  *
 *  *    http://www.apache.org/licenses/LICENSE-2.0
 *  *
 *  * Unless required by applicable law or agreed to in writing, software
 *  * distributed under the License is distributed on an "AS IS" BASIS,
 *  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  * See the License for the specific language governing permissions and
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 *
 */

package org.apache.eagle.jpm.util;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.security.UserGroupInformation;

import java.io.IOException;

public class HDFSUtil {

    public static FileSystem getFileSystem(Configuration conf) throws IOException {
        HDFSUtil.login(conf);
        return FileSystem.get(conf);
    }

    public static void login(Configuration kConfig) throws IOException {
        if (kConfig.get("hdfs.kerberos.principal") == null || kConfig.get("hdfs.kerberos.principal").isEmpty()) {
            if (kConfig.get("hadoop.job.ugi") != null) {
                System.setProperty("HADOOP_USER_NAME", kConfig.get("hadoop.job.ugi"));
            }
            return;
        }
        kConfig.setBoolean("hadoop.security.authorization", true);
        kConfig.set("hadoop.security.authentication", "kerberos");
        UserGroupInformation.setConfiguration(kConfig);
        UserGroupInformation.loginUserFromKeytab(kConfig.get("hdfs.kerberos.principal"), kConfig.get("hdfs.keytab.file"));
    }
}
